series. Plaisancien and Diceratien are minor divisions on the time-scale, which are doubtless familiar enough to the students of Pliocene or of Middle Jurassic rocks, but which may cause the ordinary geologist a journey to the public library and prolonged search. Feuerstein and Oberen Mergel-schichten are terms the meaning of which is absolutely governed by the context, or by the place in which the author happens to live; stratigraphically considered, there can be no value in such words as firestone and upper marl-beds. As for Knorrithone, it is simply a vulgar barbarism, the offspring of specialism and illiteracy, which may do well enough for the notebook of a field-geologist, but is out of place in the official publication from which it is culled. A couple of friends may talk of the 'Bel. quad, beds' or the 'corang zone,' but a sense of respect for their science, no less than a feeling for foreign readers, should keep these colloquialisms out of their serious publications.
Akin to the instance last mentioned is the slovenly habit indulged in by many zoologists of referring to a species by its trivial name alone, without mentioning the generic name, which is an equally essential component of the name of the species. This is especially a custom with entomologists of the baser sort, who, in matters nomenclatorial, seem to be capable of anything. With them as with other classes of naturalists, this apparent familiarity is probably due to their ignorance that the >ame has been applied to species of, it may be, twenty other genera. They would be less prone to the habit if they knew that zoologists of wider knowledge regard it as the hall-mark of provincialism.
What is true of geological formations and of species applies also to genera. Until the reform proposed by Prof. A. L. Herrera is adopted, the scientific names of animals and plants will not be self-explanatory. How many scientific men, asks the ingenious Mexican, outside the system-artists of the group, understand what is meant by Spinolis zena? Is it a mush room, an ant, a rose, a spider or a monkey? Some names are intended to indicate the class to which the plant or animal belongs; thus a name ending in crinus is pretty sure to belong to a crinoid, one ending in ceras may be a fossil mollusc belonging to the Ammonoidea; graptus is fairly certain to be a graptolite, and saurus a fossil reptile. The principle might well be extended, and systematists should at least refrain from applying a termination tacitly ear-marked for a particular group to a new genus belonging to an other group. If the name of an Echinoderm genus ends in cystis, the reader naturally supposes that the animal belongs to the extinct class Cystidea, and he is not a little disturbed if he discovers that it is a recent sea-urchin. However, these things are so, and will continue to be so, until people realize the responsibility that rests on the proposer of a new name. It is unnecessary to do more than recall the fact that, owing to inadvertence or ignorance, the same name has often been applied to more than one kind of organism, and may for years continue to be used in both senses, while many names well-known in zoology occur also in botanical nomenclature.
The point we would emphasize is this: Considering the difficulties that inevitably spring from such a state of affairs, it is the more incumbent on writers to explain the nature or systematic position of the organism about which they are writing. Merely to give the name, even if it chance to be correct and elsewhere unappropriated, is not enough. Still less is this satisfactory when the name has been used in more than one sense. How often does a zoologist spend time and trouble in looking up a paper on some genus in which he believes himself to be interested, only to find that the subject of the article is some different animal, or even a plant, bearing the same name. To show how real a grievance this may be, let us give
